WO2017021012A1

WO2017021012A1 - Vehicle driving-assistance method and system

Info

Publication number: WO2017021012A1
Application number: PCT/EP2016/053368
Authority: WO
Inventors: Jochen Langheim
Original assignee: Stmicroelectronics Sa
Priority date: 2015-08-04
Filing date: 2016-02-17
Publication date: 2017-02-09
Also published as: FR3039814A1

Abstract

The invention relates to a driving/assistance method for driving a vehicle (1) on a thoroughfare provided with at least one marking strip (4) for marking said thoroughfare, wherein said method includes burying a plurality of transponders (3) built into said at least one marking strip (4), equipping a vehicle (1) with at least one active communication device (2), performing a series of remote communications between said at least one active communication device (2) and said transponders (3) during the movement of the vehicle (1) on said thoroughfare, and performing a series of distance calculations between said at least one active communication device (2) and the marking strip during said series of remote communications with said consecutive transponders (3).

Description

Method and system for assisting the driving of a vehicle

Embodiments and embodiments of the invention relate to assistance with driving a vehicle, and more particularly to detection of a communication channel delimitation band.

By delimitation band is meant in particular any delimiting means equipping a communication channel, for example an emergency stop band, a median line, a dashed line, etc. This means can be temporary.

"Vehicle" means in particular any means of transport of any person, whether motorized or not, for example a motor vehicle, a truck, etc.

Driver assistance systems are active safety systems that assist the driver in his driving by automatically making certain tasks normally performed by the driver, such as the detection of lane delineation bands.

Currently there are known driver assistance systems (ADAS) embedded in vehicles and for detecting communication channel delineation bands using optical detection.

However, these systems have reliability defects, especially when the boundary strips are not sufficiently visible. For example, they may be covered by snow, their color may fade, or the reflection of light on a wet pavement may make detection impossible. In addition, some elements of the environment may be confused with a communication channel delineation mark.

According to one embodiment, a new, more reliable communication channel delineation band detection method is proposed regardless of the environment.

According to one embodiment, there is provided a method of assisting the driving of a vehicle on a communication channel equipped at least one delimiting strip of said communication channel, comprising a burying of a plurality of transponders integrated into said at least one delimiting strip, a vehicle equipment with at least one active communication device, successive communications with distance between said at least one active communication device and said transponders as and when the vehicle moves on said communication path, and successive calculations of distances between said at least one active communication device and the delimiting band as and in measurement of said successive remote communications with said successive transponders.

In other words, according to this aspect, it differs from the prior art in which the driving assistance methods comprise an optical detection of the delimitation bands, by the fact that a band detection method is proposed. delimiting device using a remote communication, for example radio frequency, between the active device (s) and the transponders.

According to one embodiment, the vehicle is equipped with a single active communication device, and each communication takes place between the active communication device and a single transponder at a time.

According to another embodiment, the vehicle is equipped with a first active device forming a transmitter and a second active device forming a receiver, the two active devices being located at two different locations of the vehicle, and each communication involves transmitter, the receiver and one transponder at a time.

Each communication comprises for example a transmission of a signal by the transmitter to the receiver, a phase shift of said signal by the transponder, and a detection by the receiver of said phase shift.

The calculation of the distance comprises, for example, a determination of the moment of entry of the transponder into the communication field of the active communication device, of the moment of exit of the transponder into the communication field of the active communication device, a calculation of the time between the moment of entry transponder in the communication field of the active communication device and the moment of exit of the transponder from the communication field of the active communication device.

According to another aspect, there is provided a system for assisting the driving of a vehicle on a communication channel equipped with at least one delimiting strip of said communication channel, comprising a plurality of transponders buried in said at least one a delimitation band, at least one active communication device located on said vehicle, said at least one active communication device being configured to communicate remotely with a succession of said transponders as the vehicle moves on said communication channel; , and calculation means located on the vehicle configured to perform successive calculations of distances between said at least one active communication device and the delimitation band as said successive remote communications with said successive transponders.

According to one embodiment, the vehicle is equipped with a single active communication device configured to communicate with a single transponder at a time.

According to another embodiment, the vehicle is equipped with a first active communication device forming a transmitter and second active communication device forming a receiver, the two active communication devices being located at two different locations of the vehicle and being configured to communicate with only one transponder at a time.

The transmitter is configured to transmit a signal to the receiver, the transponder is configured to phase out said emitted signal from the transmitter, and the receiver is configured to detect said phase shift.

The calculation means are for example configured to allow detection of the input and output times of the transponder of the communication field of the active communication device, and to calculate the duration between the input and the output of the transponder from the communication field of the active communication device.

Transponders may include integrated circuits made on flexible substrates. Thus, the impact of mechanical stresses such as those exerted on the transponders by a vehicle traveling on the delimitation strips will be limited.

The transponders can also be inserted in a means of protection against shocks.

The transponders may be either evenly distributed in the delimitation band, or randomly distributed in the delimitation band.

Advantageously, said at least one delimiting strip is a strip of paint.

In another aspect, there is provided a communication channel delineation band comprising a plurality of transponders buried in said delimitation band, the transponders being configured to communicate remotely with at least one active communication device located on a vehicle intended for to move on the said communication path near the band.

Other advantages and features of the invention will appear on examining the detailed description of the implementation and construction methods, in no way limiting and the accompanying drawings in which:

- Figures 1 to 6 illustrate embodiments and implementation of the invention.

In the remainder of the description, the terms relating to the position of the various elements of the invention are understood in relation to the usual orthogonal reference frame of motor vehicles, represented in FIGS. 1 and 3, and comprising:

- A longitudinal axis X, horizontal and directed from the rear to the front of the vehicle; - A transverse axis Y, horizontal, perpendicular to the X axis and directed from the right to the left of the vehicle moving forward:

- Z axis, orthogonal to the X and Y and vertical axis directed from bottom to top.

As illustrated in FIG. 1, a vehicle, here a car, is equipped with an active communication device 2, for example by placing it on the lower part of the right side of the vehicle 1.

A number of transponders 3 are incorporated in a painting.

The painting comprising the transponders 3 is then used to produce communication channel delineation strips 4 according to a conventional method known per se.

Thus, the plurality of transponders is integrated and distributed randomly in the delimitation bands 4.

The transponders may for example be passive devices each comprising an antenna and an integrated circuit inserted in a protective frame against shocks.

The active device 2 is configured to establish successive communications with the different transponders 3 as the vehicle moves along the boundary strips 4 and the transponders pass into its communication field.

In this example, the active communication device 2 comprises calculation means 22 and a transceiver 23. The device 2 is in communication with a transponder 31. The transceiver 23 transmits a signal 5, for example a radio frequency signal.

By reaching the transponder 31, the signal 5 is out of phase by the transponder.

The phase shift of the signal 6 is then detected by the transceiver 23. It is the detection of this phase shift which indicates to the device 2 the presence of the transponder 31 in its field of communication.

Each transponder 3 can be individually identified by the active device 2, by modulating the signal 5 in order to transmit a signal. ID. A transponder 3 may in particular use a frequency modulation in all or nothing in order to transmit bit by bit its identifier. For example, for a frequency of the emitted signal of 1 34.2 kHz, and by performing a frequency shift keying (FSK), the reflected signal 6 comprises two frequencies :

the frequency 134, 2kHz which corresponds to the transmission of a bit 0 and

the frequency 123, 2kHz which corresponds to the transmission of a bit 1.

According to one embodiment, the active device 2 can transmit a radio frequency signal having a high frequency, for example 2.45 GHz. The choice of a high communication frequency makes it possible, on the one hand, to communicate over long distances of the order of several meters, and on the other hand to exchange information at higher data rates than at low frequencies.

According to other embodiments, the communication can be done with a frequency

- from 865 MHz to 868 MHz according to ISO 1 8000-6C, or

- 13, 56 MHz according to ISO 14443 A 1-4, ISO 14443B 1-4, ISO 15693-3 and ISO 18000-3.

Communication can also be done according to the so-called "LoRa" protocol. This protocol makes it possible, using frequencies below 2.4 GHz, to transmit well through the material, which is advantageous for example when the boundary strip is covered by dirt. Information about a "LoRa" type of communication is, for example, available in the European patent application published under No. 2,763,321.

In addition, the LoRa protocol allows communications over long distances. The information sent by the transponder may include an identifier of the transponder, the position of the transponder, as well as, for example, indications of ambient temperature and humidity. It should be noted that these standards describe anti-collision algorithms, which allow the active device to handle the presence of multiple transponders in its field of communication.

FIG. 2 schematically illustrates the calculation of the distance D separating the active communication device 2 from the delimitation strip 4 when the vehicle is moving forward, calculated by the calculation means 22.

The communication or detection field 8 of the active device 2 is here schematized by a circular zone of radius R.

The value of the radius R is specific to the active device 2, and is calibrated during the manufacture thereof. However, the system can be calibrated more accurately by communicating with the vehicle's on-board computer. For example, a vehicle equipped with other measuring means can transmit said measurements to the active device in order to refine the calculations. The references 70 and 71 respectively represent the input position and the output position of the transponder 31 of the communication field 8.

The calculation means 22 make it possible in particular to determine instants T1 and T2 corresponding to the input position 70 and to the output position 71 of the transponder in the communication field. For example, when the transponder reaches the input position 70 the active communication device detects a phase shift. The calculation means therefore record the instant T l at which the phase shift takes place. When the transponder reaches the output position 71, the active device no longer detects the phase shift, and the calculation means record the time T2 at which the phase shift is no longer detected.

The calculation means 22 may furthermore comprise means for determining the speed v of the vehicle. Alternatively, the speed v can be transmitted to the calculation means by the on-board computer of the vehicle.

The calculation means 22 determine the distance D according to the formula:

D = - j R ² - v ² * T2 - T1) ² According to another embodiment illustrated in FIG. 3, the vehicle is equipped with a first active communication device 20, comprising a transmitter which is provided on the lower part of the right side of the vehicle 1, and a second active communication device 21, comprising a receiver 24 and calculation means 22, which is arranged on the lower part of the right side of the vehicle 1 so that the two devices 20 and 21 are separated for example from about 15 cm.

The use of two different devices for transmission and reception is advantageous because it allows on the one hand a greater precision in the communications, and on the other hand to replace a device independently of the other when for example a maintenance operation.

The active devices 20 and 21 are configured to establish successive communications with the different transponders 3 as the vehicle moves along the boundary strips 4 and the transponders pass into their communication field.

In this example, the active communication devices 20 and 21 are in communication with a transponder 31.

The transmitter 20 transmits a signal 5 continuously, for example a radio frequency signal. This signal is received by the receiver 24.

The phase shift of the signal 6 is then detected by the receiver 24. It is the detection of this phase shift which indicates to the device the presence of the transponder 31 in the field of communication of the active devices 20 and 21.

The calculation of the distance between the active communication devices 20 and 21 and the transponder 31 may be done in a manner similar to that described above and illustrated in FIG. 2.

The delimitation strips 4 are made for example with paint. As and when the strips of paint are made, it is possible to integrate one by one the transponders with the bands 4, spacing them for example by a few tens of centimeters.

Thus, the plurality of transponders is distributed regularly and not randomly in the delimitation strips 4. This makes it possible to prevent two transponders from being too close and generating too many collisions.

FIG. 4 illustrates a transponder 3 of which FIG. 5 is a perspective view. It comprises an integrated circuit 9, an antenna 10 and is inserted into a protective frame 1 1 against shocks.

For example, the transponder can be made on a silicon substrate, and the realization of the protection frame 11 can be integrated in the transponder embodiment process, for example by performing an elevation around the transponder 3 by resumption of epitaxy, or by etching the substrate in order to create a cavity in which the transponder is made.

It should be noted that the embodiments and implementations presented herein are in no way limiting. In particular, the mode of integration of the transponders in the delimitation bands (random or regular) can be chosen independently of the number of active devices equipping the vehicle.

Moreover, as illustrated in FIG. 6, each transponder 3 can be made on a flexible and flexible substrate after cutting a strip 12 containing all the flexible substrates.

Claims

1. A method of assisting the driving of a vehicle (1) on a communication path equipped with at least one delimiting strip (4) of said communication channel, comprising

a burial of a plurality of transponders (3) integrated in said at least one delimiting strip (4),

a vehicle equipment (1) with at least one active communication device (2),

successive successive communications between said at least one active communication device (2) and said transponders (3) as and when the vehicle (1) is moving on said communication channel, and

- Successive calculations of distances between said at least one active communication device (2) and the delimitation band as said successive remote communications with said successive transponders (3).

2. Method according to claim 1, wherein the vehicle (1) is equipped with a single active communication device (2), and each communication takes place between the active communication device (2) and a single transponder at the times.

3. A method according to claim 1, wherein the vehicle (1) is equipped with a first active device (20) forming a transmitter and a second active device (2 1) forming a receiver, the two active devices (20). , 21) being located at two different places of the vehicle, and each communication involves the transmitter (20), the receiver (21) and one transponder (3) at a time.

4. The method of claim 3, wherein each communication comprises a transmission of a signal (5) by the transmitter (20) to the receiver (21), a phase shift of said signal by the transponder (3), and a detection by the receiver of said phase shift.

5. Method according to one of the preceding claims, wherein the calculation of the distance (D) comprises a determination of the input instant (T l) of the transponder in the communication field (8) of the active communication device, the instant of output (T2) of the transponder (3) of the communication field (8) of the active device communication, a calculation of the time separating the instant of entry (T l) of the transponder (3) into the communication field of the active communication device and the instant of exit (T2) of the transponder of the communication field of the active communication device.

6. System for assisting the driving of a vehicle (1) on a communication path equipped with at least one delimiting strip (4) of said communication channel, comprising:

a plurality of transponders (3) buried in said at least one delimitation band (4),

at least one active communication device (2) located on said vehicle (1), said at least one active communication device (2) being configured to communicate remotely with a succession of said transponders (3) as and when vehicle movement (1) on said communication path, and

calculation means (22) located on the vehicle (1) configured to carry out successive calculations of distances (D) between said at least one active communication device (2) and the delimitation band as and when said communications successive successive ones with said successive transponders (3).

System according to claim 6, wherein the vehicle (1) is equipped with a single active communication device (2) configured to communicate with a single transponder (3) at a time.

The driving assistance system according to claim 6, wherein the vehicle is equipped with a first active communication device (20) forming a transmitter and a second active communication device forming a receiver (21), the two active communication devices (20, 21) being located in two places different from the vehicle, and being configured to communicate with a single transponder (3) at a time.

The driving assistance system according to claim 8, wherein the transmitter (20) is configured to transmit a signal (5) to the receiver (21), the transponder (3) is configured to phase out said transmitted signal. by the transmitter (20), and the receiver (21) is configured to detect said phase shift.

10. driving assistance system according to one of claims 6 to 9, wherein the calculation means (22) are configured to allow detection of the input (T l) and output (T2) instants of the transponder of the communication field of the active communication device, and are configured to determine the time between the input and the output of the transponder (3) of the communication field (8) of the active communication device.

1 1. Assistance system driving according to one of claims 6 to 10 wherein the transponders (3) comprise integrated circuits made on flexible substrates.

12. A driving assistance system according to one of claims 6 to 11, wherein the transponders (3) are inserted in a means of protection (1 1) against shocks.

13. Driving assistance system according to one of claims 6 to 12, wherein the transponders (3) are evenly distributed in the delimitation strip (4).

14. Driving assistance system according to one of claims 6 to 12, wherein the transponders (3) are distributed randomly in the delimitation band (4).

15. Driving assistance system according to one of claims 6 to 14, wherein said at least one delimiting strip (4) is a strip of paint.

16. Delimiting band (4) for communication path comprising a plurality of transponders (3) buried in said delimitation band, the transponders (3) being configured to communicate remotely with at least one active device of communication (2) located on a vehicle intended to move on said communication path near the band (4).